Polysilicon wire glucose sensor highly immune to interference

Abstract

This study investigated the interference elimination ability of a glucose sensor made of polysilicon wire (PSW) with a surface modified by 3-aminopropyltriethoxysilane mixed with polydimethylsiloxane-treated hydrophobic fumed silica nanoparticles plus ultra-violet illumination (γ-APTES + NPs + UV). Glucose sensing of the PSW sensor in the presence of five common interferences such as ascorbic acid (AA), uric acid (UA), acetaminophen (AP), l-cysteine (Lys), and citric acid (CA) was performed. We found that the disturbance caused by the interferences was low for interference-to-glucose concentration ratios up to 600:1 if the PSW surface is modified with γ-APTES + NPs + UV. The outstanding interference immunity of this PSW glucose sensor is believed to be mainly due to the fact that it is a dry-type sensor and the extremely low leakage of the γ-APTES + NPs membrane which allows the PSW to show three orders of magnitude lower leakage current than with the γ-APTES membrane only. In addition to its excellent interference immunity, the PSW glucose sensor with a line width of 100 nm also exhibits a wide linear detection range, an ultra-high sensitivity, an ultra low detection limit, and it can be reused more than a thousand times without much sensitivity degradation.